He is among the world's most recognised sporting figures and he earns an after-tax salary of $461,000 a week from Real Madrid. Now, Portuguese superstar Cristiano Ronaldo has taken up cudgels on behalf of a penniless Florida student who is in trouble for running on to the pitch and hugging him during a game in Miami.

His actions earned him two days in jail and charges of trespassing and disorderly conduct, which Ronaldo himself now wants dismissed after writing an emotional letter on the Albanian-born Canadian student's behalf to the Miami-Dade state attorney's office.

"My name is Cristiano Ronaldo, and I play football (soccer) for Real Madrid," the letter, obtained by the Miami Herald, begins. "I was playing at Sun Life Stadium last month when a fan entered the field. His name is Ronald Gjoka, a young college student. We hugged, and we spoke for a while, until security arrived to escort him off the field. He was not aggressive or violent in ANY way. In addition, he did not resist security or police in any possible way."

Ronaldo's letter concludes: "I am concerned because I understand he may face potential problems with immigration and with his college if the criminal charges against him are not dismissed. I understand your position and the importance of enforcing rules and laws. However, I respectfully request that you and your office reconsider this decision and dismiss the two criminal charges this young man faces. Sincerely, Cristiano Ronaldo."

The newspaper said Ronaldo's lawyers in Portugal asked the player to write the letter, then posted it after Richard Hujber, a football fan in Boynton Beach, Florida, wrote to them soon after the episode. A note from the lawyers on an embossed letterhead accompanied Ronaldo's message, to prove its authenticity.

"He [Gjoka] is just a huge soccer fan who made a mistake," Hujber told the Herald. "It was stupid what he did, but he's a really bright kid, and I would hate for these low-level misdemeanours to affect his academic future or perhaps his immigration status. Ever since 9/11 student visa holders are scrutinised much more closely."

Despite the footballer' best efforts, the case against Gjoka is set to move ahead in court in Miami on Monday. Ed Griffith, a spokesman for the state attorney's office, said Ronaldo's letter was "very, very nice" but would have no effect because he was not the aggrieved party.